1. Field of the Invention
The present invention relates to a memory card used in near field communication through single wire protocol (SWP), and more particularly to a memory card that includes a power protection unit that prevents short-circuits and power leakage between a power management unit and the SWP connection points.
2. The Prior Arts
Mobile phones are widely used electronic devices. As technology advances, the mobile phone is provided with more functions such as voice recording, video recording, photo shoot, etc. To accommodate the increasing functions, adequate memory cards are also required for data storage in the mobile phone.
Digital wallets are also becoming increasingly popular, such as debit cards used for small amount payments. The debit card uses magnetic induction to proceed to near field communication. In particular, the card can include a chip that may be powered by an external near field communication device to proceed to storage, debit and like transactions.
In this context, a current trend is the development of near field communication (NFC) mobile phones that integrate near field communication functionality in the traditional mobile phone to proceed to small amount payments. To ensure that the consumer's data are kept safe, security components are required in the NFC mobile phones. Presently, the NFC mobile phone provided by the company Google uses a Single Wire Protocol (SWP) SIM card as the security component. However, banks cannot write personalized data in the SWP SIM card. Accordingly, memory cards supporting SWP are developed for use in NFC mobile phones.
However, the voltage supply of the memory card is usually connected directly with the power source of the electronic product, which may result in the near field communication chip being easily connected directly with the voltage source. As a result, short-circuits may occur, which may damage secure data and even damage the memory card or electronic product. Moreover, because the near field communication chip and the power source of the electronic product are directly conducting, power leakage may happen, which results in insufficient driving power and incapability of driving the near field communication or the memory card.
Therefore, there is a need for a design that prevents short circuit between the connection port of the near field communication chip and the power source, as well as power leakage.